Slow-motion electrical picture reproduction



' S'LOW MOTION ELEQTRICALIGTURE REPRODUCTION 3 Sheets-Sheet l INVENTOR. year/re d /ziklai, BY y,

Aug. ZO, 1946. l G. gc. sz'lKLAl 2,406,266l

. l 's'Low MOTION ELECTRICAL PICTURE maPRoDUCTIoNv Filed Nov. 1,` 194s s sheets-sheet 2 y W ikl v l j 88 92 I A i ff'. 1 OUT/007- F y SLOW MOTION ELECTRICAL PICTURE REPRODUCTION Filed Nbv; 1', 194s s sheets-sheet s INVENT'O. l

Y I l' l 5 T TOR/YE K television system.

Patented Aug. 20, 1946 @UNITED ESTATES fluir-l?.Nrom-lcs i 2,406,266 l v SLOW-MOTION ELECTRICAL PICTURE'` Y REPRODUCTION George C. Sziklai, Princeton, N. J., assignorfto Radio Corporation of America, a corporation of -Delaware Application November 1, 1943; Serial No. 508,566 Claims. (Cl. 178--6.8)`

The present invention relates-to the reproduction ofimages electricallyand more particularly to Nincreasing ythe 'total time of reproduction of `imagesjby electrical'rmethodssogthat fast phexnomena mayv be studied. i

- Heretofore, in the reproduction Vof imagesv resenting a curverillustrating phenomenon under observation. f;

H Inf accordance with the present invention, the

ytime interval` of reproductionfoi#Y .an-image may -vary with respect to the time-interval "during which anoriginalphenomenonvoccurred, These time intervals, in accordance with the inventionA inthe preferredform, are equal orsubstantially ..equal,. and the time intervening betweenl the reproduction of a series: of i images varies and may beconsiderably prolonged. "This is permissible. since the' illusion ofv motionin any eventiL is possible onlyY because;4 of persistence of vision.

This :physiological phenomenon may be aided by ...employingr a reproducing medium having lan imagev persistence characteristic.

i `Theprimaryobject ofthe invention is tOfde-IT.

, crease-the speed of reproduction of electrically reproduced images. Y Another'object of the invention is .to` stretch the time interval normaily` 'existing between ...images of a -series --of electrically produced.:

4 imag-es.

A furtheriobject-of thepresent inventionV is to provide for tine-storage of image signals in a A .still further object of the.`v invention .is-to.,

, provide `control-means for an image.` signal storing arrangement. i

Other objects ',ofr the .invention will become 'apparent when Ithe following specificationV and claims are read in connection With the accom-zpanying drawings, wherein:

lFig. 1' is a diagrammatic illustration voi an image signal storing system embodying the present invention;

Figs. 2 and 3 are curves referred to in thef description of thepoperationof the apparatus of Fig. 1;

' Fig. 4 is a schematicshoWing-of avsystemfem- 1 2 Fig. Vfshovvs acharacteristic curve `of ayportion of Vthe apparatus of llig. `4; and

' I; Fig.Y (i1-shows.; another Amodification i alongrnthe `linesof Eig.4. i

Referring to Fig. 1 of the drawingsan .arrangefmentgisfshownin schematic-form which illustrates the basicprinciple'of the -present'invention `Reference character j I 0 indicates a device 1 for q generating an image signal-.andY is illustrated as f a; cathode raycamera or transmitter iscanning scope or-anfOrthiconPj --For examplathe genf eration.V of televisions-ignals may be-carriedout vin the manner disclosedin .a patent to Bedford,

2,192,121, ,granted- Februamaigkio. A suitable rg synchronizing arrangementisshown in a patent tofSeeleY. 2,256,530, granted September 23, v1941.

smith Patents 2,132,654.1and- 2,132,655, both camera-transmitter or scanning tube.

generatorsv *Which-,may be employed .with the These 4patents arementionedsolely because of the -fact f.vvlienfpracti ci-ngtheinvention;` The-tube l0 comi .prises a` highly-evacuated envelope l2, having.

. therein an electron gun i4 for producing an .electron beam:V and the-usual -deflecting arrangement I 6 for producing horizontal .and vertical ldeflection of,the.ray. "Theusualfsawtooth Wave generators (not shown) aswell as-control signal pulse gencraters'(-ralSoI notshovvn)` are included to furnish the.de-flecting currents or voltages to r`be applied .to thejdeflecting iunitfi. .In the latter instance the deflecting unit i6 Will.-be composed of electrostatic. deflecting vplates in space quadrature.

. vItfwill l kie-.understood that electrostatic Aor elec- .tromagneticdeflection may be employed.

.contained'infthe .envelope I2. of the subject tofbe transmitted is projected upon A mosaic. IB. oiphotoelectric elements'fis also rAn optical image the,.mosaic ylil .byffan-.optical liens.. system 2| ...W-hereby. anfelectrostaticfimage is formed on the ,.mosaic. .Thus,W-hen. the mosaicisscanned :by

the. cathode 1 ray, image .orvideosignals. areY pro- ,ducedk which-,.appear.-acrossP an output resistor 23.

-The..imagersignalsare amplified by an image V..signal,ampliliier.24, Ythe output of which is con- .nected :to the .distributor 21.

J ':Ihe subject which is .tofbescanned by-.thetube l0 is shownbyfway. of `example as a motion picture filmL 3l having. the usual successivey views 1 numbered 1 to .3 and soon. #'Whereas three frames distributor 21.

that the film 3I has been selected to simplifyVr the discussion of the operation which is to folnature of the image signals appliedto the'brush 26isshown. Each portion 59 of a signal representsthe scanning of yone frame and comprises a low. Usually, Ythe cathode ray tube .i6 will-be-'A ment which is exhibiting a pattern representing a rapidly changing characteristic curve which is to be studied. g j f jY From the apparatus thus far described, ,itwill be seen that the filmBI is moved intermittently to bring the frames I to 3 successively into position before the lens 2I.` vImage signals representing the series of `views appearing on the frames Iv4 to 3 will be amplified-by the amplifier 24 and will be furnished to the brush 26 of the A series of vstorage repeaters 3'I numbered 1 to 3, are shown asbeingY connected tol the 'contact Y -studs38 of the distributor 21. These storage repeatersmay beef anyknown" type.v For example,

the vimage multiplier camera'tube illustrated on?! page 326 (Fig. 11.16)'o,f the ,textbook Television Yby Zworykin andV Morton'published by John'V Wiley and Sons,'Inc., in-1940 mayV be used for this purpose, y

storage tubes, as disclosed by the Zworykina'ndl In using the double mosaic types of Morton reference, Aone electrnicgun structure` is v employed to Vstore a `charge image on the mosaic of the tube. The other gun structure is employed Yto scan the opposite Vside ofthe mosaic to produce signals representing the stored image. Image ori video signals may be applied to the second anode of the mosaic will assume a potential relativeto a datum level which is dependent upon the electron beam velocity as measured by the second anode voltage relative to the cathode or by the modulation of the beam when the image signal 'modulation is applied tothe control 2electrode of the gun. When the opposite side of the mosaicis 'Y scanned by the cathode ray beam cf the second gun structure, output signal energy will be derived from the second anode associatedY with the second gun structure due to release V(in of thestored charges. Y y l i Tle output connection 39 of each storage'repeater is connected to a contact stud 4I of a rotary distributor 44.l The brush arm 46 of this distributor is connected by way of a conductor 49 to the usual image signal channel of a television signal transmittingsystem which is adapted to be connected to a television signal reproducer I.

The storage repeaters 3I,` as stated above, may be of the type whichy release a storage signal upon the application of abias voltage of aselected polarity and magnitude which controls a Vbeam that known manner) v scans over the storage mosaic. This biasing voltage may be applied from a conductor 52 in communication with asuitable source of biasing po- Y vtential to the brush arm 54 of a mechanical disstud 58 of the distributor 56 over a conductor 6D.

Referring to Fig. 2 of the drawings, the general employed, to scan a ield of view havingj-movingg;A objects therein, or the screen or target of a.' cathf. p ode ray oscillograph or other laboratory instru- Vwhich is associated with the'rst gun structure, K or to a beam modulating electrode of the electron gun with the result that the individual elements to theamplier 24 after the signals 59,164,7and

section 6I Vrepresenting varying light values and the intervening line retrace section 62 during Awhich the known ylolanking *and synchronizing signals are Yto be added in known manner (not shown).

the description of the present invention.

tions per minute, the time occupied by the image portion 59V of the signal is assumed to be .03 second, and the vertical retrace time 63 is assumed to'be .005 second. Three sections orjframes of signal series 56, 64, and 66 are Vshown'whiclfmay correspond to the frames Ito 3 of thelm 3l.l

*By the arrangement disclosed in Figi 'lfthe time Vdelay between successive Signal seriesfor the several lm frames Ymaybe increased as' shown in Fig. 3 of the drawings. The Video portionS of the signal 52 is indicated by 59a and its Ybegin-Y Y ning is shown as occurring at the endojf the time interval occupied bythev signal` portion59. *The Y delay time from the beginning @fthe signal' 5s to the beginning of the signal'59q'" is"thcreiore yunder the timing'assumedby way of example,

.03 second. The time interval'63 of Fig; 2'is'V representedl at 63a onFig. 3 and is now-'.'l9""second.

Thefimage'signal representingY the second frame I 64 is indicated by'referencej'character 64a on-Fig.

3, and the next successiveframe onf-Figi. 3is 'indicated by reference character 66a. From'an inspection of Figs, 2 and 3, it'will beV seen that the scanning of frames I to 3, illustrated'by the wave form of Fig. 2, occupy oneV tenth of a-fsecond. The Atime for thev slow motion reproduction of the 'scanning ofrrames I to 3 by the television sig- `nal reproducer `5I represented by thewave 'formV rof Fig. 3 occupies a time of 470 milliseconds. To prevent operation of the video amplifier 24 until the third frame signal l66a has beenV d ischarged from the third storage repeater 31,a, cnnection 68 (Fig. 1) is provided which'is connected to'a conducting segment 69.- VA Ibrush 'armi 'I6 sweeps over this segment to apply acut olf bias 66 have' been registered.

with the distributor brush running at spietatik of 600 R. P. M., the shaft 'I2 (Fig. 1) is running at a speed of R. P. M. so that the` storage repeaters 37 are biased to discharge their stored signals in timed relationship with the' sweep of the brush 46 over the distributor segmentsflII.

Electronic switches may replace the mechanical switching means. Electronic switches per se are well known and accordingly are notillustrated in connection with Fig. 1 and are not shown in detail vin connection with Fig. y4. Suitable forms of such devices are shown by Roys et al., Patent No; 2,089,430, granted August 10, 1937, and by Shumard, Patent No. 2,146,862, grantedffFebruary 14, 1939. Y

Fig. 4 of the drawings shows diagrammatically the preferred embodiment of the invention.l In

this ligure the output of vthe amplifier 24 of Fig.-

. 1 isY applied to a switching circuit '16.1 This Only three sections of 6I Iand 62 are shown illustratively, but it will be understood that many more of these actually willV be included.`

lThe exactjnumber is more or less immaterial in Patent :No;:,;2,113;011z to? White,\fsgrantedf-Apri1 5,

1938. .5p-Aiserieszofgsignal Istorageiltubes 18-is .is For; illustrativeapurposesy three "ofsthentubes 'I8 are shown by'lig.' 4".' of ther drawings; and these ubes maybeemployed to store' thesignals. from '....three successive scanning :operationsof the trans- A`:zmittingit scanner 510; A'Iubes .ofV this' general type i. arefillustrated an'd;describedin al Britishipatent 'Unitedf States fpa'tent to` Harry `Branson,.. No. i 2257,562, granted September v30'; 1941.

Each tube' 18! vis lprovided'withian electron gun constructonii I zand includes. a source .of cathode f; rays 182, a .contro1"'grid83,r and anuario-de 4or ac- I0; or any scanning' source. A-s a-matter ofiact, I

the target may be' scanned in a vfashiontzliiiferent from the line byline method for example; spiral L or other curvilinearffashions are applicable.

- `.Varyingpotentialsare. applied under the control offthe video signals to the grid electrode 83, herein considered asthecontrol electrode,.to"con trol'the intensity of the velectron bearnemitted .from the 'cathodeemitteru82lin proportion to the light value of the image being scanned. In l order to 'focus suitably the fllcathode ray, the Husual focusing 'electrodes .including the electrode .84 are provided as shown in Fig. 4 of the Branson i patent referred to above. The conical'innervportion of the .tube envelope 88 is in the form of a control electrode or where' desired a separate 'electrode'QI of conicalV shape is provided. Adjacent theend portion of the tube there is-suitalbly vsupported a mosaic electrode' IEN) which includes an insulating lplate S2 lupon which is. suitably deposited a coating 93 otiisolated globules. Immediately behind the insulating plate member 93 there is positioned a conducting: :sign-al plate lmember.C93. To all of the electrodes@suitable connectionsto supply'operating and control voltages are made. The grids 83 of each tube are biased to a diierentl negative value by a corine'ctionlill` so `that in order to remove thebias and render the tubec55 f operative, different external positive biasing v-voltages are provide-d from'the switching circuit 16. Referring to'Fig. 5 of the'drawings; the bias on eachsuccessive tube applied by its connection is illustrated by the curve 102. purposes of illustration that a zero biasapplied to thegrid 83 of each tube will operate, that is tofsay, the cathode ray beam in that tube will becomeactive and may be modulated by1voltage Variations applied to its grid.V The curve'l 03 rep-1 `:resenting the output of the countercircuit which f isadded algebraically to the bias. on eachf grid increasesin the positive direction by successive steps as shown-'so that each tube 18 in the series becomes successively operative. In thism'anner` It is iassumed fori;

styf 173,111.9@offiwhicl'r.I is@maintained'isubstantially 'f onstant. .y Y n ,y

yethei collector..l anode 9 Iii-duringV the scanning the.ibeami.when it is'y vmaintained at constant intensity and is fedltoathe'egrid of `an amplifier eztube. :.One. :amplifier tube-is .shown for f each of .1 the,vv sto-ragetub'es .18. 'I'he'rst storage tubeout- .v put from its collector 9|. sis". fed over a conneclolxtion; 'I 06.: tothe :grid 1I 0810i `an amplifiertube I 09. The outputs ofithe remaining storage tubesof the series arefconnected r-espectivelytor grids `I. I I)` and i I;I I1, ofgaimplientubes .I I2 and 114.-

2 'I'he-amplifyingtubesV |09, y I I2,\. and .I-'IIILV are 15-f..biased.; .to ,.cutl oil?l by.. signals? from .the switching e* circuit'appliedover connections AI I5, I I6,Jand AII [during.lallztimesr except when. the correspondzingrstor-ageiltubes are discharged .and .the electricalimpulses :corresponding to the delayed Kpic- :20....turenframe1 are :toI be transmitted to'the1line amplifier.

With'. thearrangement.'shown inv Fig. 4.'.controlled; in apreferredzm'anner from an electronic wswitching, .circuit. I6 .fratherlthan by mechanical distributors asin Fig. `1,' of` the drawings, amore Hflexible, timingvof` the successive steps in thesop- "eration may be` realized..Y ,For` exam-ple, with the l scanning .tube I0 'operating at normal'television scanning frequencypinterlacedl or 'non-interlaced, 30` the signalVK 59;. of=y Fig.;` 2; will-occupy `approximately one thirtieth of: axsecon-d,` and the retrace time f631 Willormay occupyr.approximately one lonehund-red twentieth iof a' second. The consta-ntsof the'switching ycircuitV may 'bexselected "VI-eso.- that'thesignal 59aY occupies one thirtiethof a second-whiletthetime-s delay ybetween the `sig-- -nals 69a^and64a occupiesone tenthiof asecond.

This will result "in aconsiderable slowing down of .the imagereproducedzini the image lsignal reeproducingfdevice IIB. Y Aszvhas beenstated in connection withfthe'ap- `fparatus 0f `Fig. l of thefdrawings,V the series of Y ,image signals such: as;signals-59.,` 54, 66, etc.,.may beincreased` to any-:amount by. .increasing the numberwof imagexstorage tubes`-118f The 'image 11storageitubesmaybevery compact, particularly ..--where.spiralscanning is employed asV pointed'out above,Ik .and also; :their :operationzdoes not` depend on photoelectric action which also permits mate- `:rialreductioninsize. h Afbankw of such tubes 'may l' #fbefarranged .together in arelatively small space. 'Il he switching circuitxcanbe easily expanded with. additional.. multivibrators` to accommodate v-additional storage tubes 18. 1

A.Ihefunc-tion of the `switchingcircuit shown onf.Fig. 4 is as follows: It connectsfthe grids of kthe storagetubes successively to the outputof .then the. grid. ofthe second .tube-forthe. second` trarne,- etc. After oneV frame signalqis applied to a tube, itis.blanked by biasing .thegrid to cut off until itsdischarge cycle occurs. By using counter circuits, multivibrators, or the like l.in the switching circuit 16, a square wave steppulse is `applied'tol the tubes insuccessionz as shown `tubesli! and amplifier tubes IGS, II2, and II4 "tronic'conduction willv take place only when an `-adequately large positive ksignal isapplied to their respective grids. `Thegrids 83 of the storage Y tubes 'ljare'suicientlypositive during the charging-and dischargingrperiod,"controlled by multi- Thetstoragessignal 'from eachk tube is collected on the curve: E03 of Fig; 5." Since the storage are biasedback to different negative values, elec- Fig. 5.' n Y VThe blocking oscillators |46 and |41 are then r triggered by the output ofthe counter circuit and since the pulse width is equal to the frame period,K they apply a square wave on the grids 13: vibrators 'or'blocking.;oscillators'runningat a 's'uitable frequency, determined by the time `difference betweenjthe charge and `discharge interval', while ,they grids |03, I l; and of amplier tubes.i|09, I |.2,I and I4 are biased beyond 'cut on' atY all timesV 'except the 'discharge'tperiod' p.

i Blockingpscillators in combinationswith counter circuits are fully describedin the White patent above referred to.

f A'modied arrangement of the preferred emjbodiment of the inventiondisclosedpin Fig.4 is shown byr Fig. 6.

This modiiication discloses vsomewhat inl detail an electronic switching and control circuit for controllingthe operation of image :storage ltubes such, for example, asfareV indicated by reference character 18 in'Fig.' 4.

With a View to simplifying the drawings, only two of. these tubes |26 and |21 are shown. vIt will sbe understood, as stated previously in. connection with Figs. 1 Yand 4 of the drawings, that the number of these tubes Vwill be determined by the number of successive kimages 'of the rapidly occurring phenomenawhich are' to be stored. i

Composite signals rfrom a transmittersuch as the cathode ray scanning tube I0 of Fig. 1 of the drawings are applied to' the grids of the storage tubes |26 and r|21 throughamplirlers |3| and |32. These composite signals are also applied through an integratingA circuit v|33 to a tube |34.

The function of this'integrating circuit is toremove the video and horizontal synchronizingand blanking signals from the vertical duration pulses.

s The signal on the .plate |36 of the tube |34 will appear, accordingly, as indicated on the drawings,

' above the tube |34. These signals. are designated 59and 63'; whereasthe incoming successive imi age signals are designated 59 an'dBS andappear above the input connection |38.

, :The pulses 59and 63 Yare fed to counter circuits |39 and |4| andv will producea potential increase in a series of steps designated 59, 63

`as shown by the curve appearing above the tube oscillator tubes |46 and |41 which are biased by These potentials-arc then fed to blocking sources of biasing potential shown conventionally as batteries |48 and |49 respectively. These batteries have potentials of opposite sign correspond-v ing to the counter circuit output as shown in of the storage `tubes |26 and |21. In placeof arblocling oscillator, any other type of relaxaj.

tionl oscillator may be used, such as multivibrators, dynatrons, pulsing gas discharge tubes, etc.,

provided their pulse width is approximately equal Vto theframe period, and the oscillating rate is comparatively slow.

" 'IVhekarrangement just described provides for thev application of a vpositive potential to the A proper grids ofthe proper storage tubes I 26and j|21 at the time of transmission of successive frames.

' A relaxation oscillator such as the multivibrator has a repetition rate equalto the desired speed of the slow motion image. By way of example, 'this was indicated in connection with Fig. 3 as being 220 milliseconds and the pulses generated by this multivibrator arethen applied to counter circuits |52 and |53 which trigger the multivibrators |56 and |51 successively in the manner in which the tubes |42 and |43 triggered blocking oscillators n x The pulse widthtof ithe relaxationoscillatorsV |56 .and |51is istillequal to'the 1framepriod;"but .Y the repetition rate is considerably slower rvthan t delayed pulses'are fed to' the gridsof. the storagey f y tubes |26 and |21 and, alsotothegridsofathef,Vv amplifier tubes v|59 'and;|6'|. It wi11-be:;seen" is .and l 4.1, except J f layed time rate.

that: of the original 'frame frequency. 21g-These that each. storage tubeis` bias'edpbackl at alltimes, except fortwo pulsescoinciding with `the recording storage time-and', the dischargetime' 'The amplifier 'tubes stai and 1.6 1*-.are biaseaf'sbacii at all times except duringA therdischargeperiod: 1,.; i In the slow motion systems' of'this invention, the higher.l the initial rate at which thesuccessive 1 images are stored,`determined forexample inFig.

' l bythe field frequency-applied :tothe deflection means of the tube l0, the more the observing rate may be reduced. Y., It will benoted that while signals representing-each frame or field of the image are discharged fromthe storage device at theroriginal rate at which they were stored, initiation' :of the discharge of each field orframe is delayed or lretarded as .compared to its rate of storage. 1

Various modifications of thesystern shown-' and described herein by way'of example are possible,

without departing from the spirit and scopefof the invention d-escribedhereimand it is'desired that 'anyland allof such-modications be'convsidered Within the purview. of the present invenn tion defined by the hereinafter appended fclaims.

Having now described the invention,.what is claimed and desiredto be secured by lLetters Patent is the following: v v

l. In a system .for'reproducing images electrically in slow'motion, means to storeV at a given f rate signals representing Vsaid images to record successive steps of'motion occurring in the images at the rate of occurrence'of themotion, f

quentially, and means for the increasingly delayed initiation of the discharge at the original storage rate of the said storage signals. 6,3.. In afsystem `for reproducing images electri- .cally,means for generating, at a given rate, a

series Aofi image signals in accordance with an optical image appearing in a field of view, means for storing said ima-ge signals sequentially to record successive steps of motion occurringin the /imagesat the rate of voccurrence of the motion,

means for discharging signals representative of said stored signals, said discharge' occurring'- at the same rate as the storage-of said signals and in the same sequence', and means for producing a time delay between each one YYof, said series of discharge signals whereby the mo-tion appears to occur lat a rate differing-from the; rate of occurrence.'

4. In a system for reproducingimages electri- Y cally,V means for generating a series of image signals in accordance. with an optical image appearing in a field vof view and at a predetermined rate, means for storing said image signalssequentially, means for discharging signals representative of said stored signals said discharge occurring at the same rate as the storage of said signals, and means for the increasingly delayed initiation of the discharge at the original storage rate of the said storage signals.

5. In a system for reproducing images electrically, means for receiving a series of image signals representing a viewed image, a series of storage repeaters for storing said image signals sequentially, means for causing repetition of said stored signals sequentially at the rate of storage, and means :for the increasingly delayed initiation of the discharge of said stored signals.

6. In a system for reproducing images electrically, means for receiving, at a given rate, a series of image signals representing a viewed image, a series of storage repeaters for storing said image signals sequentially, means for causing repetition ci' said stored signals, said repetition occurring at the same rate as the storage of said signals and in the Same sequence, and means for producing a time delay between each one of said series of repeated signals.

7. A slow motion television transmitting system comprising a television pickup tube including a target electrode, means to generate a cathode ray beam, means to deflect said cathode ray beam in mutually perpendicular directions to scan said target electrode at a predetermined rate to produce image signals, a plurality of storage tubes each including a storage electrode, means to store the produced image signals on the storage electrodes of said tubes as electrostatic charges, means to remove said stored signals at a rate corresponding substantially to the rate of storage, and means for producing a time delay between the removal of a stored signal from one storage tube and the removal of a signal from the successive storage tube.

8. A slow motion television transmitting system comprising a television pickup tube including a light sensitive target electrode, means to produce an electrostatic charge image of a scene to be transmitted on said target electrode, means to generate a cathode ray beam, means to deiiect said cathode ray beam in mutually perpendicular directions to scan said target electrode at a predetermined rate to produce image signals, a plurality of storage tubes each including a storage electrode, means sequentially to store the produced image signals on the storage electrodes of said tubes as electrostatic charge image replicas of the image scanned in the said pickup tube, means sequentially to remove said stored image signals at substantially the same rate as the original productio-n and storgae rate, and means to produce a time delay between the removal of a stored signal from one storage tube and the removal of a signal from a successive storage tube.

9. A slow motion television transmitting system comprising a television pickup tube having a target electrode, means to generate a cathode ray beam in said tube, means to deflect said cathode ray beam in horizontal and vertical directions to scan said target electrode to produce image signals, a plurality of storage tubes each including a storage electrode, means including a switching arrangement successively to store the image signais produced during a number of vertical deiiection signals on a separate storage tube, means including a second switching arrangement to remove said stored image signals in succession at a rate substantially equal to the rate at which they were originally produced, and means to produce a time delay between the removal of a stored signal from one storage tube and the removal of a stored signal from the successive storage tube.

10. A slow motion television transmitting system comprising a television pickup tube having a light sensitive target electrode, means to generate a cathode ray beam in said tube, means to deflect said cathode ray beam in horizontal and vertical directions at different ratesto scan said target electrode to produce image signals corresponding to each television line and frame in accordance with the horizontal and vertical deflections of said cathode ray beam, a plurality of storage tubes each including an electron storage electrode, means including a switching arrangement operable sequentially to store the produced image signals representative of each television frame at the horizontal and vertical deflection rates on a separate storage tube, means including a second switching arrangement operable successively to remove said stored image signals at substantially the same rate as the rate at which they were originally produced and stored, and a switching arrangement controlling the initiation of each signal removal operation, the time of initiation being delayed from frame to frame of said storage cycle.

GEORGE C. SZIKLAI. 

